No-spill drinking products are well known in the art. In the past, a variety of such products have been developed and marketed. In general, the goal of a no-spill cup is to provide a construction which minimizes or prevents liquid from emerging out of the cup when liquid flow is not desired, i.e. when the user is not drinking. However, though the assemblies of the prior art are intended to avoid such accidents, their construction is such that they generally do not provide a secure enough protection against undesirable spilling or leakage. Thus, when such cups are inverted, or more significantly, when they are shaken vigorously, liquid will often emerge from them. This can be a particular problem with young children, for whom these cups are usually intended.
To address this problem, the present inventor has previously provided various advances in the art, as disclosed for example in U.S. Pat. Nos. 6,321,931 and 6,357,620, both of which are fully incorporated herein by reference. Further thereto, yet further improvements in the art of such no-spill drinking products are provided herein.
Moreover, while such drinking products have been generally sold as products for older children, leakage is currently also major problem with present baby bottles and bottle nipples. Most nipples have a hole in the top that fluid is drawn out of. If the bottle is not in an upright position, however, the bottle will leak. For example, if a mother mixes the contents of a baby bottle and then places that baby bottle into her diaper bag, the bottle will leak if the bottle falls over on its side or if the diaper bag is not standing straight up. The liquid from the bottle will then spill into the bag or into the bottle's cap.
Similarly, if a baby takes the bottle out of his or her mouth and lays it down, or if the bottle falls out of the baby's mouth, liquid will leak out of the nipple onto the surrounding floor, carpet, car seat, or so forth. Various different kinds of nipples are known in the art, the nipples varying depending on the type of liquid that the nipple is intended to be used with. Thus, nipples exist for use with water, milk, juice, and formula. Yet, leakage is a very significant problem with all of the various nipples currently available commercially.
If the baby falls asleep with a bottle, the milk can leak out of the bottle. This liquid could undesirably leak onto the baby and/or surrounding area. Furthermore, if the bottle were in the baby's mouth when he or she fell asleep, any liquid that leaked out could potentially choke the baby.
Accordingly, it would be a significant improvement in the art to provide a design allowing the construction of nipples and baby bottles which would eliminate leakage. It would be a further improvement to provide nipples which adjust to the various consistencies of the different liquids provided to children.